Machine for making box blanks



Se t. 25, 1956 w. J. GOETTSCH MACHINE FOR MAKING BOX BLANKS 2Sheets-Sheet 1 Filed Feb. 20, 1953 Sept. 25, 1956 w. J. GOETTSCH MACHINEFOR MAKING BOX BLANKS 2 Sheets-Sheet 2 Filed Feb. 20, 1953 2 W 4 f- 5ATTORNEY 4 mm M N m R m %N. fi, 1%2 |Umwzw WEE- 4 4 mm F 1 1% Q QM M m n\Q a J R A @N \T l b w 36% m mud mm k W\ ww @9529. $-mor05 0* w Nacho:0% NW. m. \N V m R mm L w G um mo 6 W mmwm SN QN QN QR \N n L: @QEI Q IF QQEI .|.r QM Q, 6N RQ QQL United States Patent MACHINE FOR MAKING BOXBLANKS Walter J. Goettsch, Kenilworth, Ill., assignor to Samuel M.Langston Co., Camden, N. J., a corporation of New Jersey ApplicationFebruary 20, 1953, Serial No. 338,030

2 Claims. (Cl. 154-1) This invention is an improvement in machines ofthe type shown and claimed in my Patent 2,309,728, granted Feb. 2, 1943,and used for producing and continuously advancing a web of stiff sheetmaterial, slitting and scoring it, and then cutting it transversely intosuccessive sections constituting box blanks.

In the machine of that patent and in the present invention there areprovided a series of operating units which act in succession on thestiff sheet as it is continuously produced and advanced. These include acutter at the delivery end of the double facer, and whichis operated tosever the web just before the slowing down of the double facer and theadjusting of the other units for making box blanks of a different sizeor shape.

Beyond this cutter there is provided a slitter andscorer of the generaltype shown in the Behrens Patent 2,291,-

789,, and having a plurality of sets of slitting and scoring bladesmounted on different radial arms of a rotatable frame, and provided withgears for transmitting power to those blades which are in operatingposition. A motor is provided for rotating the frame to swing one set ofblades out of operative position after a given number of blanks of onesize or shape have been cut, and swinging another set into positionpreparatory to starting the making of blanks of a different size and/ orshape, and a separate motor is provided for rotating the blades of aslitter-scorer.

Beyond the slitter-scorer is a unit which has separate portions fortransversely cutting into sections the strips separated by the slittingblades, and thus form the box blanks. This cut-off may be of the typeshown in the Behrens Patent 2,262,913, and has a motor to adjust thetiming of its operations so as to cut off longer or shorter sheets. Amain motor is provided for driving the double facer, the cut-off at thedelivery end thereof, and the blades of the units which cut the scoredstrips into separate box blanks; and a plurality of small motors areprovided for adjusting these units.

A plurality of connected motor-driven cams are employed to close andopen the switches of the various solenoids in the proper sequence, andthese open and close the switches of the various timing motors. Thesecams may be relatively adjusted to provide the proper sequence ofoperations.

When it is desired to bring into position a different set of preadjustedslitting and scoring blades and/ or to adjust the. units which cut theslitted and scored strips into sections, the web is severed, and thedifferential is operated to slow down the double facer, but withoutslowing down the severed sections of the web. Thus a gap is formed, andwhen thegap is at the slitter-scorer a motor on the latter is operatedto bring a different set of blades into operating position. When the gapis at the unit which cuts the scored strips into sections a motor isoperated to adjust this unit.

The main objects of the present invention are to simplify and reduce thecost of the mechanism required for effecting all of the adjustmentsnecessary for the making of blanks of a different shape and/or size; topermit the use of a simpler and cheaper slitter-scorer; to secureincreased accuracy in the making of the adjustments while the machine isrunning at reduced speed, and to reduce the time required for making theadjustments. This time saving is particularly important where themachine must be frequently adjusted to make small batches of blanks ofdifferent sizes or relative proportions, and it is also important thatthe time the sheet remains in the double facer during the making of theadjustments be reduced to the minimum, as overheating tends to make theblanks brittle.

As one feature of the present invention the cut-ofi at the delivery endof the double facer is provided with a motor for operating it when it isdesired to adjust the units which act on the web.

As a further feature of the invention the differential is of the motordriven type, and is positioned in the main drive between theslitter-scorer and the unit which cuts the slitted and scored stripsinto sections. This may be operated to slow down the double facer afterthe web has been cut in two at the delivery end thereof, but the cut offsection continues to travel at a higher speed than that of the web so asto form a gap and permit a different set of slitting and scoring bladesto be brought into operative position.

As a further feature the slitting and scoring blades are normally drivenfrom the main motor, but a separate motor is provided for keeping therotational speed of these blades the same as the linear speed of thesevered section of the web after the web has been transversely severedand the double facer has been slowed down, and until the rear end of thesevered section has passed the slider-scorer.

While the machine is operating to make blanks for boxes of a particularshape and size the preselector on the slitter-scorer and the cut-off areset for the adjustments required for the next order of blanks for boxesof different proportions. After bringing the machine to a predeterminedspeed a motor is energized to give the cam shaft one revolution. Duringthis revolution the cams control the stopping and starting of thereversible adjusting motors, and then the machine is brought up tonormal operating speed.

A machine embodying the invention is shown somewhat diagrammatically intheaccompanying drawing, in which:

Fig. l is a schematic plan view of the machine.

Fig. 2 is a side elevation.

Fig. 3 is a section on the line 3-3 of Fig. 1.

Figs. 4a, 4b and 4c show the knife blades in three positions throughwhich they pass, and the associated control switch; and

Fig. 5 is a wiring diagram of the controls for the motors and otherunits.

The various units acting on the sheet may be of the same generalcharacter as those shown in my patent above referred to, except ashereinafter noted. In these 'units, as shown in Figs. 1 and 2, the stiffsheet of double faced corrugated board is produced in the double facer1t), and between belts on pulleys 11 and 12, and is delivered through ashear 13 which, as previously noted, is operated only at the completionof one order and preparatory to making adjustments for the next order.The board then passes through the slitter-scorer 14 and then to thecut-oil 15, which is driven from the line shaft 42, and the finished boxblanks are discharged onto a conveyor 17. In some cases there may be twocut-offs, each acting on a different one of the strips which have beenseparated at the slitter-scorer 14, and two conveyors, one from eachcut-off.

As in my patent above identified, various of the sec- 3 tions may beadjusted by motors to form different sizes and types of blanks. Thecut-off 13 has a pair of rotary knives 19 and 20 which may be rotatedthrough a single revolution by a motor 21.

The slitter-scorer is preferably of the type shown in Behrens Patent2,291,789, and in Figs. 11 and 12. of my Patent 2,309,728, and in whichthere are three sets of cutting and scoring blades, each set being on adifferent pair of shafts mounted on a separate pair of radial arms.Thus, while the blades on one pair of arms are operating on a web, thoseon another pair of arms may be adjusted to the extent required for thenext order of box blanks. Beyond the slitter-scorer 14 the web passes tothe cutoff mechanism. The cut-off unit 15 may be of the type shown inFig. 16 of my Patent 2,309,728, and may be adjusted by a motor 24 to cutthe web into sections of the desired length, and equal to the peripheryof the desired box.

The double facer is driven by a large D. C. motor 30, the speed of whichis determined by the voltage applied to its armature by a D. C.generator. The voltage, and therefore the speed of the motor, isadjusted by a rheostat 31 operated by a motor 32.

As one feature of the invention means are provided for controlling thismotor 32 and the various adjusting motors. This means includes a timermotor 33 which operates a plurality of circuit closing cams 34, 35, 36,37, 38 and 39 mounted on a shaft 48.

As another feature of the invention a differential 41 is positioned inthe main drive shaft 42 from the motor 30 to the double facer 10 and theslitter-scorer 14, and this differential is provided with a motor 43which when operated in one direction will cause the shaft section 42leading to the double facer and the slitter-scorer to rotate slower thanthe portion between the differential and the main motor 30. Thus, whenthe required number of blanks of one size and shape has been made, thedifferential may be operated to slow down the double facer 10preparatory to cutting a different size or shape of blank, and While theother units are being appropriately adjusted. At the time the operationof the differential begins the motor 21 is operated to give the knives19 and one revolution to sever the web transversely at the delivery endof the double facer, but as hereinafter described, the slitter-scorerwill maintain its previous speed. For this purpose there is provided anauxiliary motor which will maintain the speed of the blades so that theywill advance the severed section and form a gap between the web and thesevered section.

When the severed section has advanced in respect to the now slowerrunning double facer to form a gap, and that gap has reached theslitter-scorer, the motor 27 of the latter is operated to swing one setof slitting or scoring blades out of position and another, which has hadits blades adjusted for the next job, will swing into positionpreparatory to starting the next order for blanks which differ in someparticulars from those of the preceding order.

The blades of the splitter-scorer 14 are normally driven from thesection 42' of the main drive shaft which is beyond the differential 41,and through a chain 44 and gears 44', so as to have a peripheral speedequal to the linear speed of the web. As one feature of the inventionmeans are provided for maintaining this rotational speed after thesection 42' of the main shaft has been slowed down by the differentialand the web has been cut in two, and so that the blades will act toadvance the severed section while slitting and scoring it. For thispurpose there is provided a motor 45 for driving the slitting andscoring blades through a chain 46, and with normal peripheral speed, sothat the blades act on and also advance the severed section until theend of the latter has passed said blades. To permit this driving of theslitter-scorer at a faster speed than that of the shaft 42' after thelatter has slowed down, there are provided two overrunning clutches 47and 48, the clutch 47 being between the motor 45 and the gears 44 andthe other clutch 48 being between the shaft 42' and gears 44. Thus thespeed of the severed section is not changed when the shaft 42' slowsdown, because the motor 45 maintains the speed of the slitter-scorerblades and that of the severed section until after that section haspassed said blades.

From the foregoing it will be seen that there are a plurality of motorswhich are intermittently operated to make the various adjustments.Before these adjustments are made the motor 21 is operated to sever theweb at the discharge end of the double facer 10. Motor 43 then operatesthe differential to slow down the double facer. Motor 27 is thenoperated to swing one set of slitter-scorers out of position and anotherset into position, and motor 24 is operated to readjust the cut-off forlonger or shorter box blanks.

In Fig. 5 there is illustrated a wiring diagram for the operation andtiming of the various motors of the machine. In this specific embodimentD. C. current is supplied through the lines 50-51 for operating thereversible rheostat motor 32 and certain of the control units, and A. C.current is supplied through the lines 5253 for operating the cam drivingmotor 33 and various solenoids which effect the control of the operatingparts of the machine. The motor 32 operates the movable element of therhetostat 31 through a shaft 56, which to avoid confusion isdiagrammatically illustrated in dotted lines. The rheostat motor 32 isdirectly connected to the line 50, and is connected to the line 51through lines 54 and 55 which include the field coils 59 and 60 of themotor 32, and also include push buttons or switches 57 and 58 wherebythe rheostat may be rotated in either direction to increase or decreasethe speed of the machine.

The rheostat has three segments a, b, and c, which are wiped by amovable contact d operated by the motor 32. Segment a is connected tothe line 55 including field coil 59 and segment 0 is connected to theline 54 containing field coil 60. By operating one or the other of thepush buttons 57 or 58 the rheostat motor may be manually controlled torotate in the desired direction to increase or decrease the speed of themotor 30. To permit bringing the speed to a predetermined one, thecenter segment 11 of the rheostat is connected by a line 61a to asolenoid 61 which operates a switch 62 in a line 63 leading to the timermotor 33 and to the circuit controlled by the cam 34.

When the motor 30 is slowed down, the movable contact member of engagessegment b, the time delay relay coil 61 is energized, opening switch62a, so that the relay coil 64 is no longer energized, and the switch 62is closed to start the timer motor 33. When the circuit of coil 64 isopened it opens the circuit of the time delay relay coil 61, but thiscoil 61 maintains contact for a short delaying period before it dropsout. By this time cam 34 has rotated far enough to close switch 34a, sothat when switch 62 opens the motor 33 continues to run for the durationof the program cycle. When coil 61 is de-encrgized switch 62a recloses,but coil 64 remains de-energized because contact 68 has opened.

The lines 50 and 51 of the direct current circuit are connected througha solenoid 64 and a push button 65 in parallel with the two switches 67and 68 which are energized by the solenoid 64 when the latter isenergized by the closing of the push button 65. Thus the push button maybe immediately released and the switches 67 and 63 will be held closeduntil switch 62a is opened. The switch 68 closes the circuit throughline 69 to the movable member d of the rheostat 31. The preset speedfeature may be cut out of the circuit by a switch 70 movable to connectthe lines 50 and 51 through pilot light 51a.

When the switch 62 is closed by solenoid 61 current 7 'may flow from theline 53 through the motor 33, lines 72 and 63, switch 62 and line 71 tothe line 52, and the program switch control motor 33 will startrotation. This causes the cam 34 promptly to close the switch 34a whichis in parallel with the switch 62 and the latter may open, but thecircuit of the timer motor 33 will remain closed for one revolution, anduntil the cam 34 opens the circuit at 34a. The motor 33 also rotates thecams 35 to 39 which are set to close the circuits of the variousadjusting motors, and in the proper sequence, and to hold them closedfor the time required to make the necessary adjustments for the nextorder of blanks.

The cam 35 closes a switch 35a so that current may flow from line 53through line 72 and a solenoid 73 to the line 52. This solenoid closesthe circuit of the auxiliary motor 45 which drives the slitting andscoring blades of the slitter-scorer 14 through chain 46 at a peripheralspeed of for instance 200 feet per minute, after the differential 41 hasoperated to slow down the shaft 42' which normally drives the blades.This driving of blades by either the shaft 42' or the motor 45 ispermitted by the overrunning clutches 47 and 48.

In Figs. 4a, 4b and 4c the rotary heads of the rotary shear 13 are shownas viewed from the opposite side of Fig. 2. The cutter 19 or the shafttherefor has a cam 79 which operates to control the circuit of the motor21 of the cutoff. Normally the cutter is at rest and in the positionshown in Fig. 4a; the circuit of the motor 21 is open; and the sheet maypass freely between the blades.

When cam 36 closes the contacts 36a the rotary knives 19 and 20 make onerevolution through successive positions shown in Figs. 4a, 4b and 40 tosever the web. Current is supplied through line 80, and the switches 77and 77a are normally closed. When cam 36 closes switch 36a solenoid 75is energized through line 74, cam operated switch 77 and line 76. Theenergized solenoid closes switches 78 and 78a. Switch 78 remains closedafter switch 36a opens, so that the motor 21 of the cut-off 13, whichhas been started by the closing of switch 78a, continues its rotation.The solenoid 75 also opens switch 77a in the circuit of a solenoid 82.

Starting from the position shown in Fig. 4a the motor 21 rotates cutterheads 19 and 20 to the position shown in Fig. 4b, where the blades coactto sever the web. The heads continue to rotate to the position shown inFig. 40, at which point cam 79 opens switch 77, thereby deenergizingsolenoid 75, whereupon switches 78 and 78a open and switch 77a closes.The opening of switch 78a disconnects the motor 21 from the line, andthe closing of switch 77a energizes solenoid 82 through plugging switch83, which is closed when the motor 21 is running at full speed. Theenergizing of solenoid 82 closes contacts 81 which reverse the flow ofcurrent to the motor 21 until such time as the speed of motor 21 hasdropped almost to the point at which it starts reverse rotation, atwhich time plugging switch 83 opens, leaving motor 21 at rest andstopping the cutting heads in the position shown in Fig. 4a. Thisplugging switch may be of the type shown in General Electric Co.Bulletin (IR-2962.

In parallel with the cam-operated switch 36a there is provided a pushbutton switch 84 whereby if desired the shear motor may be operatedindependently of the control by the switch 36a, for instance to cut offan irregular end section.

As soon as the web is severed the cam 37 operates to close a switch 37ain a line 35 connecting lines 52 and 53, and in this line is a solenoid86 for closing the switch 87 in the circuit of the differential motor43. The action of the differential is such that it opposes that of themain motor and slows down the double facer, for instance to a speed of30 feet per minute, without slowing down the slitter-scorer, and thusforms a gap in the sheet, permits rotation of the frame of theslitter-scorer, and brings a different set of blades into operativeposition. As soon as the tail of the severed web passes the slitter, cam35 stops the auxiliary motor 45. When this motor stops, the clutch 47overruns and the drive shaft picks up the slitter drive through theoverrunning clutch 48.

At the completion of one order the frame is rotated to move one set ofblades out of operating position and another into position, thedirection of rotation being dependent upon which of the sets of bladeshas been adjusted for the next order. Therefore the motor 27 forrotating the frame of the slitter-scorer is a reversible one.

The cam 33 controls the starting time of motor 27 which acts to bringinto operating position the slitting and scoring blades which have beenadjusted for the next batch of blanks. Current for the motor is suppliedthrough line 89 and flows in either one direction or the other to themotor 27, depending on which of the switches 91 or 92 is closed. Theseswitches are operated by solenoids 93 and 94, and current from line 53may be directed to either solenoid by a pre-selector switch 95 in serieswith the switch 38a, which is operated by the cam 38. Either of thesolenoids 93 and 94 may be momentarily closed by operating the pushbutton switch 96 or the switch 96, so that in case the blade carryingframe does not stop in exactly the desired position it may be joggedalong in the desired direction, and to the desired extent.

The cam 39 is for controlling the adjusting of the unit 15 which cutsthe slitted and scored web into sections, each of the proper lengthcorresponding to the periphery of the desired box. This unit may be ofthe same type as each of the units 12 and 13 in my patent 2,309,728, andhas a reversible motor 24 corresponding to one of the motors 255 in Fig.16 of said patent, for adjusting the frequency of operation of thecut-01f blades, and therefore the length of the blanks. There may be asecond one of these units. In that case the wiring associated with cam39 will be duplicated and controlled by an additional cam similar to cam39.

The cam 39 at the proper time closes contacts 97 which permit current toflow from the line 53 through normally closed push button switch 98 andthen through a switch 99 and the contacts 97 to a preselector switch100. This may be positioned to direct the current from line to eitherthe solenoid 101 or 102, and through line 100' to the line 52. Thesesolenoids act to close either the switch 103 or 193 to actuate motor 24in one direction or the other for adjustment as desired of the frequencyof operation of knives which cut the strips into sections of the properlength for the box blank. The switch 99a corresponds to switch of theBehrens Patent 2,320,710, and is opened to stop the motor 24 when thepreselected sheet length has been'reached.

When an order is completed the main motor 30 is at a speed correspondingto 200 feet per minute, and when the movable member of the rheostat isin the central position it closes the circuit of the coil 61 to closethe switch 62 and start the motor 33. The switch 62 may immediatelyreopen, as the circuit of the motor will then be closed by the cam 34 assoon as the motor starts.

Preliminary to starting the continuous running feature and before themachine has been slowed down, the oporator makes the followingpreparation:

1. The cam-operated preselector switch 95 on the slitting and scoringattachment is set to the forward or reverse position, depending upon thedirection in which the frame must be rotated to bring one or the otherof the two idle pairs of shafts into position for the next order.

2. The cut-off preselector to switch 99a is set according to the sheetlength desired for the next run, and the long-short selector switch 109is set to the appropriate position.

3. The hand-automatic selector switch 99 on the cutoff is set to theautomatic position.

4. The hand-automatic selector switch 70 on the master control panel isset to the automatic position. When this is done the pilot light 51agoes out, indicating that the setup is in readiness for the automaticcycle to begin.

The cycle is initiated by momentarily pushing the run button 65 whichcompletes a circuit from line 51 through relay coil 64, switch 62a andselector switch 70 to the line 50. Energizing coil 64 causes contacts67, 68 to close. The upper contact 67 parallels the push button 64, sothat even though the push button is released the coil 64 remainsenergized.

From the foregoing it will be seen that the sequence of operationseffected by the series of cams is as follows:

1. The main motor 30 is brought to that speed which will advance the webabout 200 feet per minute, at which time the motor 45 of theslitter-scorer is at rest, the clutch 47 is overrunning, and the clutch48 is driving the slitterscorer.

2. The cam 34 operates the switch 34a which holds the circuit of themotor 33 closed during one complete .revolution of the cams, so that theswitch 62 may be reopened.

3. The cam 35 closes the circuit of the auxiliary motor 45 of theslitter-scorer.

4. The cam 36 then closes the circuit through the solenoid 75 whichcloses the switches 78 and 78a, whereupon the shear motor 21 at thedelivery end of the double facer severs the web.

5. The cam 37 then closes the circuit of the motor 43 and starts thedifferential, which slows down the double facer to about 30 feet perminute, but the motor 45 continues to drive the slitter-scorer at about200 feet per minute to slit the section which has been cut off.

6. When the end of the severed section passes the slitter the cam 35opens the circuit of the auxiliary motor 45, and the clutch 48 acts todrive the slitter-scorer at about 30 feet per minute.

7. The cam 38 then operates to close the circuit of the motor 27, andthe frame of the slitter-scorer is rotated in one direction or theother, depending upon the setting of the switch 95, and to bring intoposition the set of blades which have been adjusted for the next order.

8. The cam 39 then closes to operate the motor 24 in one direction orthe other to operate the cut-oh? more or less frequently, as shorter orlonger sheets may be required.

9. The cam 37 then opens contacts 37a to stop the differential motor.

10. The cam 34 then operates to open the circuit of the motor 33, andthe latter will remain at rest until the order for one type of blankshas been completed and the main motor has been slowed down, and theswitch 62 is again closed.

For adjusting the machine to cut longer sheets the switch 100 is in theposition shown in Fig. 5, and the adjusting motor 24 will rotate in onedirection. For adjusting the machine to cut shorter sheets the switchHit) is moved to the opposite position, and the solenoid 102 will beenergized to close the switch 163' to rotate the adjusting motor 24 inthe opposite direction.

If it is desired to make adjustments by hand the switch 99 is moved tothe right to cut the contact 9'7 out of circuit and bring the pushbutton switch 104 into the circuit. Thus, by moving the switch 100 tothe right or to the left and momentarily depressing push button 164,either switch 103 or 103 may be momentarily closed. This entire controlmay be cut out by opening push button switch 98.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

1. In a machine comprising feed mechanism for continuouslylongitudinally advancing strip material and a second mechanismrelatively spaced from the feed mechanism along the path of travel ofsaid material and operative upon the latter, said second mechanismcomprising a plurality of operating heads and means for selectivelyshifting said heads into operative position with respect to said strip,a cut-off means for said strip in proximity to said feed mechanism andbetween the latter and the said second mechanism and operativeindependently to sever the said strip, a common drive shaft for saidmechanisms, auxiliary drive means for the second mechanism and means foractuating said auxiliary means to operate said mechanism independentlyof the common drive shaft and at a rate of speed corresponding to thenormal operating speed of the common drive shaft, means for reducing thespeed of said common drive shaft, and means for automatic coordinatedoperation of said cut-off means, auxiliary drive means, the saidhead-shifting means, and the means for reducing the speed of the driveshaft, to cut off the web, to simultaneously actuate the means forreducing the speed of the drive shaft and to initiate operation of saidauxiliary drive means so as to reduce the speed of the feed mechanismwhile maintaining the relatively high operating speed of the secondmechanism, to subsequently interrupt the operation of the auxiliarydrive means after the cut ends of web have been separated by thedifferential speeds of the feed mechanism and second mechanisms to arequired extent so as to reduce the operating speed of the secondmechanism to the reduced speed of the drive shaft, to thereafter actuatethe said headshifting means to bring a selected operating head intooperative position between said cut ends of web, and to interrupt theoperation of the shaft speed reducing means so as to restore theoperating speed of the shaft and the said mechanisms.

2. A machine for making box blanks including a double facer for makingand continuously delivering a web of stiff sheet material, web cut-ofifmeans at the delivery end of said double facer and independent motormeans for operating said cut-off means, a unit for slitting and scoringthe advancing web, said unit comprising a plurality of slitting andscoring heads operative individually on said web and motor means forshifting said heads selectively into the operative position, a commondrive shaft for the double facer and said slitter-scorer unit, a maindrive motor for said shaft, means for operatively connecting the doublefacer and the slitter-scorer unit individually to said shaft, the meansfor connecting the slitter-scorer unit to the shaft comprisingoverrunning clutch means providing for operation of the said unit byauxiliary drive means independently of and at speeds corresponding tothe normal operating speed of said common shaft, auxiliary drive meansconnected to the slitter-scorer unit, means including a differentialgear unit interposed between the said drive shaft and the main drivemotor and separate motor means for driving said differential to reducethe speed of the shaft independently of the main drive motor, and meansfor automatic coordinated operation of said cut-off means, differentialunit, auxiliary drive means, and head-shifting means, to cut off theweb, to simultaneously actuate the differential unit and the auxiliarydrive means to reduce the speed of the drive shaft and of the doublefacer while maintaining the relatively high operating speed of theslitting and scoring unit, to subsequently interrupt the operation ofthe auxiliary drive means after the cut ends of web have been separatedto a required extent so as to reduce the operat ing speed of theslitting and scoring unit to the reduced speed of the drive shaft, tothereafter actuate the said head-shifting motor means so as to bring aselected slitting and scoring head into operative position between saidout ends of web, and to interrupt the operation of the differential unitso as to restore the operating speeds of the double facer and theslitting and scoring units.

(References on following page) References Cited in the file of thispatent UNITED STATES PATENTS Laabs Mar. 20, 1934 Fairchild Aug. 21, 19345 Gulliksen Aug. 11, 1936 Pecker May 18, 1937

